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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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98                                 ALASKAN GLACIER STUDIES
General Description. Immediately north of Turner Glacier, and between it and Hub-bard Glacier are two much smaller glaciers, each of which, however, is a great deal larger than Galiano Glacier. The southernmost of these has been named Haenke, the other had no name until now.1 Both of these glaciers have their sources in numerous small tributaries, some of them cascading, which are fed from the extensive snowfields that cover the lofty mountains to the northwest of the head of Disenchantment Bay. Haenke Glacier is the longer of the two, its grade is also steeper than that of its neighbor, and it is set more deeply in its valley. Both are normal valley glaciers, and until 1906 both extended almost to the ends of their valleys, but failed to reach the fiord, from which they were separated by alluvial fans built by the streams to which their melting gave birth. In each case the strip of alluvial fan was a half mile to a mile wide, measured from the glacier front to the fiord, and the fans proved conclusively that these glaciers had not recently been tidal, for many years must have been required to build such broad, perfect, alluvial fans. Although they appear in the photographs of previous expeditions, these glaciers had not, until 1906, attracted enough attention in this region of much larger, more accessible glaciers, to have been given descriptions or even names.
From the photographs taken prior to 1906 it is perfectly clear that in 1891, 1899 and 1905 these two glaciers were essentially stagnant at their lower ends, which were covered with an extensive waste of black shale ablation moraine, much as Black Glacier still is. Par up the mountain valley, in each case, there was abundant crevassing, and in the upper reaches of each there was evidence of distinct activity; but for two or three miles from the fronts of the glaciers there were no crevasses that could be seen from the distance at which these glaciers were observed and photographed.
Advance of Miller Glacier. In 1905, Miller Glacier showed some crevassing which we interpreted as a possible evidence of an advance, and this tentative conclusion was strengthened by the fact that the front of the glacier on the 1905 photographs from Haenke Island was apparently farther forward than in the 1899 photographs. We therefore wrote in the first draft of this report, as follows.-—"It is possible that between 1899 and and 1905 this glacier had undergone an advance as a result of earthquake shaking, and that by the latter year its effects had been so healed by ablation as to be no longer noticeable. Possibly had we been on the outlook for evidence of such an advance in 1905, and had then been as familiar with the effects of an advance as we are now, we might have detected it."
We have subsequently obtained possession of a photograph taken by Ensign C. R. Miller in 1901, in which it is clearly evident that in the early summer of that year Miller Glacier was profoundly crevassed, quite in contrast to its condition in 1899 and in 1905. There can be no question, therefore, but that between 1899 and 1901 Miller Glacier was trans-forme^ by crevassing, and that between 1901 and 1905, ablation had so reduced the crevassing that it could not be certainly proved by photographs alone. It thus seems to fall in the series of advancing glaciers of the Yakutat Bay region, and about in the position in that series in which, from its small size, one would be inclined to place it—that is
* To it we propose to give the name Miller Glacier after C. R. Miller, who, in charge of a U. S. Fish Commission expedition in 1901, took the photograph from which we have been enabled to discover an important episode in its history.